Phosphor wheel, light source unit, and image display device

ABSTRACT

To provide a phosphor wheel capable of restraining vibration caused by a driving unit for rotatably driving a wheel and reducing noise in a high frequency band. The phosphor wheel includes: a wheel substrate that has a surface on which a fluorescent material is provided; a driving unit that rotates the wheel substrate; a support portion that supports the driving unit and is fixed to a housing; and a buffer member that is provided to fill a space between the support portion and a part of the housing.

CROSS REFERENCES TO RELATED APPLICATIONS

This application is a continuation of and claims the benefit under 35U.S.C. § 120 of U.S. patent application Ser. No. 16/236,132, titled“PHOSPHOR WHEEL, LIGHT SOURCE UNIT, AND IMAGE DISPLAY DEVICE,” filed onDec. 28, 2018, now U.S. Pat. No. 10,436,421, which is a continuation ofand claims the benefit under 35 U.S.C. § 120 of U.S. patent applicationSer. No. 15/816,318, titled “PHOSPHOR WHEEL, LIGHT SOURCE UNIT, ANDIMAGE DISPLAY DEVICE,” filed on Nov. 17, 2017, now U.S. Pat. No.10,203,093, which is a continuation of and claims the benefit under 35U.S.C. § 120 of U.S. patent application Ser. No. 15/321,456, titled“PHOSPHOR WHEEL, LIGHT SOURCE UNIT, AND IMAGE DISPLAY DEVICE,” filed onDec. 22, 2016, now U.S. Pat. No. 9,851,075, which is the National Stageof International Application No. PCT/JP2015/058902, filed in theJapanese Patent Office as a Receiving Office on Mar. 24, 2015, whichclaims priority to Japanese Patent Application No. JP 2014-137613, filedin the Japanese Patent Office on Jul. 3, 2014 which are herebyincorporated by reference in their entirety.

TECHNICAL FIELD

The present disclosure relates to a phosphor wheel, a light source unit,and an image display device.

BACKGROUND ART

In recent years, a projector device has been widely known as an imagedisplay device for displaying a projection image on a plane ofprojection such as a screen. The projector device is used not only inoffices but also in homes and has various display formats such as a CRTmethod, a liquid crystal method, a DLP method, and an LCOS method.

Such a projector device includes various driving units such as motors.For example, there are motors for rotating a color wheel that spectrallydisperses light from a light source in accordance with a transmissionproperty and a phosphor wheel on which a fluorescent material isprovided, the fluorescent material being material that, when thefluorescent material is irradiated with light in a particular wavelengthregion, emits light in a wavelength region different from that of thelight. When vibration is generated by driving those driving units, noiseis generated from the projector device in some cases. Therefore, removalof noise caused by the driving unit has been studied.

For example, Patent Literature 1 discloses a color wheel device in whicha metal plate member is provided between a motor for driving a colorwheel and a mounting plate fixed to an optical unit. In PatentLiterature 1, vibration is restrained by increasing the weight of thecolor wheel device with the use of the metal plate member. For example,Patent Literature 2 discloses a fan retention structure in which avibration isolation sponge is interposed between suction-side anddelivery-side tubular frames of an axial-flow fan.

CITATION LIST Patent Literature

Patent Literature 1: JP 2009-265137A

Patent Literature 2: JP 2008-190434A

SUMMARY OF INVENTION Technical Problem

However, in Patent Literature 1 described above, the motor is supportedby the mounting plate in a cantilevered state, and therefore vibrationof the motor is easily transmitted to the optical unit and the like.Further, it is difficult to apply a technique disclosed in PatentLiterature 2 described above to a color wheel, a phosphor wheel, or thelike.

In view of this, the present disclosure proposes a phosphor wheel, alight source unit, and an image display device, each of which is new, isimproved, and is capable of restraining vibration caused by a drivingunit for rotatably driving a wheel and reducing noise in a highfrequency band.

Solution to Problem

According to the present disclosure, there is provided a phosphor wheelincluding: a wheel substrate that has a surface on which a fluorescentmaterial is provided; a driving unit that rotates the wheel substrate; asupport portion that supports the driving unit and is fixed to ahousing; and a buffer member that is provided to fill a space betweenthe support portion and a part of the housing.

According to the present disclosure, there is provided a light sourceunit including: a light source; and a phosphor wheel that includes afluorescent material that, when the fluorescent material is irradiatedwith light emitted from the light source, emits fluorescence emissionlight in a different wavelength region. The phosphor wheel includes awheel substrate that has a surface on which the fluorescent material isprovided, a driving unit that rotates the wheel substrate, a supportportion that supports the driving unit and is fixed to a housing, and abuffer member that is provided to fill a space between the supportportion and a part of the housing.

According to the present disclosure, there is provided an image displaydevice including: a light source unit that includes a light source and aphosphor wheel including a fluorescent material that, when thefluorescent material is irradiated with light emitted from the lightsource, emits fluorescence emission light in a different wavelengthregion; and an optical system that projects an image formed on the basisof a luminous flux emitted from the light source unit onto a plane ofprojection. The phosphor wheel of the light source unit includes a wheelsubstrate that has a surface on which a fluorescent material isprovided, a driving unit that rotates the wheel substrate, a supportportion that supports the driving unit and is fixed to a housing, and abuffer member that is provided to fill a space between the supportportion and a part of the housing.

Advantageous Effects of Invention

As described above, according to the present disclosure, it is possibleto restrain vibration caused by a driving unit for rotatably driving awheel and reduce noise in a high frequency band. Note that the effectsdescribed above are not necessarily limitative. With or in the place ofthe above effects, there may be achieved any one of the effectsdescribed in this specification or other effects that may be graspedfrom this specification.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic configuration diagram showing one configurationexample of an image display device including a light source unitaccording to an embodiment of the present disclosure.

FIG. 2 is a schematic perspective view showing one configuration of thelight source unit according to this embodiment.

FIG. 3 is a schematic plan view showing one configuration of a lightsource section of the light source unit according to this embodiment.

FIG. 4 is a partially enlarged perspective view showing a configurationof a phosphor wheel according to the present embodiment.

FIG. 5 is a perspective view showing the phosphor wheel according to thepresent embodiment, the phosphor wheel being stored in a housing.

FIG. 6 is a side view of the phosphor wheel according to thisembodiment.

FIG. 7 is a plan view of the phosphor wheel according to thisembodiment.

FIG. 8 is an explanatory view showing one configuration example of abuffer member.

DESCRIPTION OF EMBODIMENT(S)

Hereinafter, (a) preferred embodiment(s) of the present disclosure willbe described in detail with reference to the appended drawings. In thisspecification and the appended drawings, structural elements that havesubstantially the same function and structure are denoted with the samereference numerals, and repeated explanation of these structuralelements is omitted.

Note that description will be provided in the following order.

1. Configuration of image display device

2. Configuration of light source unit

3. Noise reduction in light source section

4. Conclusion

1. Configuration of Image Display Device

One configuration example of an image display device 1 including a lightsource unit 10 according to an embodiment of the present disclosure willbe described with reference to FIG. 1. FIG. 1 is a schematicconfiguration diagram showing one configuration example of the imagedisplay device 1 including the light source unit 10 according to thepresent embodiment.

The image display device 1 according to the present embodiment is oneconfiguration example of a projector that condenses light from a lightsource for emitting light, emits the light through a projection lens viaa device for displaying an image, and projects an image on a displaysurface such as a screen S. The image display device 1 shown in FIG. 1is one configuration example of a projector including a 3LCD as amicrodisplay.

Light emitted from the light source unit 10 passes through an integratorlens 2 including a first lens array 2 a and a second lens array 2 b inorder to maintain brightness also in edges of a display image, thenpasses through a polarization conversion element 3 a and a condenserlens 3 b, and is separated for each wavelength region.

The light that has passed through the condenser lens 3 b is incident ona first reflection dichroic mirror 4 a that reflects only light in a redwavelength region and causes light in the other wavelength regions topass therethrough. Thus, the light in the red wavelength region isreflected by the first reflection dichroic mirror 4 a to travel to areflection mirror 5 a. The light in the red wavelength region is furtherreflected by the reflection mirror 5 a to be incident on a liquidcrystal panel 6 a for red.

The light in other wavelength regions, which has passed through thefirst reflection dichroic mirror 4 a, is incident on a second reflectiondichroic mirror 4 b. The second reflection dichroic mirror 4 b reflectsonly light in a green wavelength region and causes light in the otherwavelength region, i.e., light in a blue wavelength region to passtherethrough. The light in the green wavelength region reflected by thesecond reflection dichroic mirror 4 b is incident on the liquid crystalpanel 6 b for green. The light in the blue wavelength region, which haspassed through the second reflection dichroic mirror 4 b, is reflectedby reflection mirrors 5 b and 5 c and is then incident on a liquidcrystal panel 6 c for blue.

The liquid crystal panels 6 a to 6 c for respective colors modulate thelight that has been incident thereon in accordance with input imagesignals and generate signal light beams of an image corresponding toRGB. For the liquid crystal panels 6 a to 6 c, for example, atransmissive liquid crystal element including a high temperaturepolysilicon TFT may be used. The signal light beams modulated by theliquid crystal panels 6 a to 6 c are incident on a dichroic prism 7 andare combined with one another. The dichroic prism 7 is formed as arectangular parallelepiped by combining four triangular prisms so as toreflect the red signal light beam and the blue signal light beam andcause the green signal light beam to transmit therethrough. The signallight beams of the respective colors combined by the dichroic prism 7are incident on a projection lens 8 and are projected as an image on thedisplay surface such as the screen S.

In the image display device 1, the liquid crystal panels 6 a to 6 c andthe dichroic prism 7 function as a light modulation combination systemfor modulating and combining incident light. The integrator lens 2, thepolarization conversion element 3 a, the condenser lens 3 b, thereflection dichroic mirrors 4 a and 4 b, and the reflection mirrors 5 ato 5 c function as an illumination optical system for introducing lightfrom the light source unit 10 to the liquid crystal panels 6 a to 6 cconstituting the light modulation combination system. In addition, andthe projection lens 8 functions as a projection optical system forprojecting an image emitted from the dichroic prism 7.

2. Configuration of Light Source Unit

As the light source unit 10 of the image display device 1, a lightsource device using fluorescence emission light generated by irradiatinga fluorescent material with light from a solid state light source isused in this technique. One configuration example of the light sourceunit 10 will be described with reference to FIG. 2 and FIG. 3. Note thatFIG. 2 is a schematic perspective view showing one configuration of thelight source unit 10 according to the present embodiment. FIG. 3 is aschematic plan view showing one configuration of a light source section10A of the light source unit 10 according to the present embodiment.

As shown in FIG. 2, the light source unit 10 according to the presentembodiment includes the light source section 10A for emitting light anda cooling section 10B for cooling the light source section 10A. In thepresent embodiment, as shown in FIG. 3, the light source section 10A isa reflective light source device using a fluorescent material.

As shown in FIG. 3, the light source section 10A according to thepresent embodiment includes a first light source 102 and a second lightsource 104 as light sources. Note that, although FIG. 3 only shows thesingle first light source 102 and the single second light source 104,the present disclosure is not limited to this example. One or aplurality of first light sources 102 and one or a plurality of secondlight sources 104 may be provided. The first light source 102 is a lightsource for irradiating (exciting) a fluorescent material, and, forexample, a laser may be used. The first light source 102 is a lightsource for causing a fluorescent material (reference sign 152 in FIG. 4)for modulating a wavelength to efficiently emit light, and, in thepresent embodiment, a laser for the blue wavelength region is used. Asthe fluorescent material, for example, a YAG-based fluorescent materialis used.

The second light source 104 emits light in a wavelength region of colorthat is insufficient in the first light source 102 and fluorescenceemission light caused by the fluorescent material. In the presentembodiment, the second light source 104 is a laser for emitting light inthe blue wavelength region.

Light emitted from the first light source 102 is incident on a firstdichroic mirror 122 constituting the light source section 10A throughlenses 112 and 113. The fluorescent material 152 provided on a wheelsubstrate 151 is irradiated with the light that has been incident on thefirst dichroic mirror 122 from the first light source 102 through lenses142 and 143 (see FIG. 8), thereby generating light in two wavelengthregions. The lenses 142 and 143 are arranged on an optical path the sameas that of the first light source 102, and the first dichroic mirror 122is arranged between the first light source 102 and the lens 142. Thefirst dichroic mirror 122 is provided to have an inclination of about45° with respect to, for example, the optical path between the firstlight source 102 and the lenses 142 and 143. The fluorescent material152 is arranged so that light is condensed by the lenses 142 and 143into the fluorescent material 152. At this time, in order to improve acooling performance of the wheel substrate 151, it is preferable tocondense light by using the lens 143 in the vicinity of a peripheralportion of the wheel substrate 151 than to condense light in thevicinity of the center thereof.

The light emitted from the first light source 102 is incident on a firstsurface 122 a of the first dichroic mirror 122. The first dichroicmirror 122 causes the light of the first light source 102 which has beenincident on the first surface 122 a to transmit therethrough. Further,the first dichroic mirror 122 reflects, on a second surface 122 b,fluorescence emission light caused by the fluorescent material 152 thatis arranged to face to the first light source 102 via the first dichroicmirror 122 and the lenses 142 and 143 and reflected light of the firstlight source 102. The light emitted from the first light source 102passes through the first dichroic mirror 122 and is condensed by thelenses 142 and 143, and therefore the fluorescent material 152 isirradiated with the light.

The fluorescent material 152 is a YAG-based fluorescent material and,when the fluorescent material is irradiated with light in the bluewavelength region by the first light source 102, absorbs the light andemits light in a wavelength region different from the blue wavelengthregion. The fluorescent material 152 is applied to, for example, thedisc-shaped wheel substrate 151 made of metal such as aluminum. Thefluorescent material 152 may be applied only to the peripheral portionthereof or may be applied to the whole surface thereof.

The wheel substrate 151 constitutes a phosphor wheel 150 rotated about arotating shaft 155 provided at the center thereof as the center ofrotation by a motor 154 serving as a driving unit. This is a mechanismfor preventing light emission efficiency of the fluorescent material 152from being reduced because the wheel substrate 151 is heated byirradiation with light and preventing resin for use in adhesion betweenthe wheel substrate 151 and the fluorescent material 152 from beingmelted. By rotating the wheel substrate 151 and rotating the fluorescentmaterial 152, it is possible to improve the cooling performance of thewheel substrate 151 and improve the light emission efficiency of thefluorescent material 152.

The fluorescence emission light emitted by the fluorescent material 152is, for example, light in a yellow wavelength region and passes throughthe lenses 143 and 142 to be incident on the second surface 122 b of thefirst dichroic mirror 122 together with the light in the blue wavelengthregion reflected by the wheel substrate 151 without being absorbed bythe fluorescent material 152. In that case, by providing a function ofrotating or disturbing polarized light when light in the blue wavelengthregion is reflected by a surface of the wheel substrate 151, the lightcan be efficiently reflected by the first dichroic mirror 122. The firstdichroic mirror 122 reflects the fluorescence emission light and thereflected light incident on the second surface 122 b toward a lens 145.

Meanwhile, light emitted from the second light source 104 is incident ona second dichroic mirror 124 through lenses 114 and 115. The lenses 114and 115 are arranged in order on an optical path the same as that of thesecond light source 104, and the second dichroic mirror 124 is arrangedon an extension line thereof. The second dichroic mirror 124 reflectsthe light incident from the second light source 104 and causes the lightto be incident on the first dichroic mirror 122 through a transmissivewheel 130 and a lens 144. That is, the second dichroic mirror 124 isprovided at a position at which a direction of incident light from thesecond light source 104 intersects with arrangement directions of thefirst dichroic mirror 122 and the lens 145. At this time, the seconddichroic mirror 124 is provided to have an inclination of about 45° withrespect to optical paths of the second light source 104 and the lenses114 and 115 so that, for example, the second dichroic mirror 124 issubstantially symmetrical to the first dichroic mirror 120.

The light of the second light source 104 reflected by the seconddichroic mirror 124 is incident on the first dichroic mirror 122 throughthe transmissive wheel 130 and the lens 144. Then, the light of thesecond light source 104 passes through the first dichroic mirror 122 andis combined with an emitted light beam from the first light source 102,the emitted light beam being composed of the fluorescence emission lightand the reflected light. The combined light is emitted from the lightsource section 10A through the lens 145.

3. Noise Reduction in Light Source Section

Herein, the image display device 1 includes a plurality of driving unitsto drive a cooling fan, a phosphor wheel, a color wheel, and the like.When those driving units are operated at the time of use of the imagedisplay device 1, driving sound is generated. Driving sound of thedriving units has such a low volume that the driving sound does notbother a user in the first place, or the driving units are arranged in asealed space so that sound is hardly transmitted from the sealed spaceto the outside, and therefore the driving sound does not give anunpleasant feeling to the user of the image display device 1 in mostcases. However, for example, in the case of a driving unit arranged in aspace that is not sealed, vibration sound of driving sound may becomenoise.

As the driving units of the image display device 1, there are motors forrotatably driving a color wheel and the phosphor wheel 150. The motorsthereof generate motor noise at high frequency of about 6000 Hz in somecases. High-frequency sound tends to be perceived as harsh sound, andtherefore it is desirable to reduce such sound. In view of this, inorder to reduce noise of the motor 154 of the phosphor wheel 150, thelight source section 10A according to the present embodiment includes abuffer member 160 for restraining vibration generated at the time ofdrive of the motor 154 from being propagated to a housing of the lightsource unit 10. Hereinafter, a configuration of the phosphor wheel 150including the buffer member 160 and a function of the buffer member 160will be described.

The configuration of the phosphor wheel 150 including the buffer member160 according to the present embodiment will be described with referenceto FIGS. 4 to 8. Note that FIG. 4 is a perspective view showing thephosphor wheel 150 according to the present embodiment, the phosphorwheel being stored in the housing. FIG. 5 is a partially enlargedperspective view showing the configuration of the phosphor wheel 150according to the present embodiment. FIG. 6 is a side view of thephosphor wheel 150 according to the present embodiment. FIG. 7 is a planview of the phosphor wheel according to the present embodiment. FIG. 8is an explanatory view showing one configuration example of the buffermember 160.

The phosphor wheel 150 according to the present embodiment is a memberfor reflecting light incident from the first light source 102 as lightin a predetermined wavelength region by using the fluorescent material152. The fluorescent material 152 is annularly provided in the vicinityof a peripheral portion of a surface of the wheel substrate 151, thesurface being positioned on a side on which light is incident from thefirst light source 102. In the phosphor wheel 150, as shown in FIG. 4,the wheel substrate 151 on which the fluorescent material 152 isprovided is arranged in a space formed by wheel storage portions 12 aand 12 b. The wheel storage portions 12 a and 12 b are members whosefacing surfaces are recessed and store the disc-shaped wheel substrate151 so as to interpose the wheel substrate 151 therebetween.

A lens support portion 12 c is connected to the wheel storage portions12 a and 12 b. The lens support portion 12 c supports the lenses 142 and143 through which light incident on or reflected by the fluorescentmaterial 152 of the phosphor wheel 150 passes. As shown in FIG. 4 andFIG. 7, the lens support portion 12 c is fixed to the wheel storageportions 12 a and 12 b so that optical axes of the lenses 142 and 143are orthogonal to the fluorescent material 152 of the phosphor wheel150.

As shown in FIG. 5 and FIG. 7, a motor support portion 12 d supportingthe motor 154 is provided in the lens support portion 12 c. The motorsupport portion 12 d is provided to extend from one surface of the lenssupport portion 12 c toward the motor 154. At this time, the motor 154is supported by the motor support portion 12 d so that the rotatingshaft 155 of the motor 154 is orthogonal to the optical axes of thelenses 142 and 143.

Herein, a distance between the lenses 142 and 143 supported by the lenssupport portion 12 c and a surface of the phosphor wheel 150 influencesbrightness of light emitted by the light source unit 10. Therefore, itis desirable to form those members so as not to destroy an optimalpositional relationship between the lenses 142 and 143 and the phosphorwheel 150 in the light source unit 10. In the present embodiment, thelens support portion 12 c and the motor support portion 12 d areintegrally formed to maintain a positional relationship between thelenses 142 and 143 and the motor 154 for driving the phosphor wheel 150.Thus, it is possible to achieve optimal brightness of light emitted bythe light source unit 10 according to the present embodiment.

As shown in FIG. 4, the phosphor wheel 150 stored in the wheel storageportions 12 a and 12 b is fixed to a housing 14 of the light sourcesection 10A together with the lenses 142 and 143 supported by the lenssupport portion 12 c and the motor 154 supported by the motor supportportion 12 d.

Herein, the light source section 10A according to the present embodimentincludes the buffer member 160 between the motor 154 supported by themotor support portion 12 d and the housing 14. FIG. 5 shows the phosphorwheel 150 in which the wheel storage portions 12 a and 12 b are removed.As described above, the motor 154 for rotatably driving the phosphorwheel 150 is supported in a cantilevered state by the motor supportportion 12 d provided to be extend from the lens support portion 12 csupporting the lenses 142 and 143. Therefore, vibration of the motorsupport portion 12 d, which is caused by rotatably driving the motor154, is larger than vibration that is caused when the motor supportportion 12 d is assumed to be supported on both sides. The vibration ofthe motor support portion 12 d is propagated to the lens support portion12 c and then to the housing 14. Further, the motor 154 of the phosphorwheel 150 generates high-frequency noise in many cases, and thishigh-frequency sound is amplified while being propagated from the motorsupport portion 12 d to the lens support portion 12 c and then to thehousing 14.

In view of this, in the light source section 10A according to thepresent embodiment, as shown in FIG. 5, the buffer member 160 isarranged between a back surface side of the motor 154 supported by themotor support portion 12 d (a side opposite to a side of the rotatingshaft to which the wheel substrate 151 is provided) and the housing 14facing thereto. Thus, noise of the motor 154 is prevented from beingpropagated to the housing 14 of the light source section 10A, andhigh-frequency sound is prevented from being amplified.

The buffer member 160 is made of a shock absorbing material such asrubber or sponge and is a member filled between the back surface side ofthe motor 154 and the housing 14 facing thereto. When the buffer member160 is provided, noise of the motor 154 is absorbed by the buffer member160, thereby restraining the noise from being propagated to the housing14 and being amplified.

As shown in FIG. 8, the buffer member 160 according to the presentembodiment is formed by bonding two sheet members 162 and 164 differentin harness via, for example, an adhesive agent or a double-sided tape.The first sheet member 162 provided on the motor 154 side is softer thanthe second sheet member 164 provided on the housing 14 side. Because thefirst sheet member 162 is made of a soft material, it is possible to fitthe buffer member 160 to the motor 154 serving as a generation source ofnoise and effectively absorb noise. In addition, when the sheet members162 and 164 different in harness are bonded as in the presentembodiment, it is possible to effectively attenuate noise in a boundarysurface between the first sheet member 162 and the second sheet member164.

For example, when comparing the case where the buffer member 160 isprovided with the case where the buffer member 160 is not provided, avolume of noise generated from the light source unit 10 is substantiallythe same in a low frequency band of about 1000 Hz or less. However, whenthe frequency exceeds about 2000 Hz, noise generated in the case wherethe buffer member 160 is not provided is increased to exceed anallowable range. On the contrary, noise generated in the case where thebuffer member 160 is provided falls within the allowable range.

In the case where the whole buffer member 160 is made of a material thesame as that of the first sheet member 162 or the whole buffer member160 is made of a material the same as that of the second sheet member164, noise is generated as compared with the case of a double structurein the present embodiment, but the noise is restrained as compared withthe case where the buffer member 160 is not provided. Also in the casewhere a hard sheet member is used on the motor 154 side and a soft sheetmember is used on the housing 14 side, noise is generated as comparedwith the case of the double structure in the present embodiment, but thenoise is restrained as compared with the case where the buffer member160 is not provided.

Regarding hardness of the first sheet member 162 and the second sheetmember 164 constituting the buffer member 160, for example, the softfirst sheet member 162 may have about 35 to 45 degrees and the hardsecond sheet member 164 may have about 80 to 90 degrees (both are AscarC hardness). Although thicknesses of the first sheet member 162 and thesecond sheet member 164 are not particularly limited, the first sheetmember 162 and the second sheet member 164 may have, for example, thesame thickness.

Note that, although, in FIG. 8, the buffer member 160 is formed bybonding the two sheet members 162 and 164, the present disclosure is notlimited to this example, and, for example, the buffer member 160 may beformed by laminating a plurality of sheet members. Also in this case,the harness of a sheet member in contact with the motor 154 only needsto be at least softer than that of sheet members bonded thereto. Thethickness of the buffer member 160 and the harness of each sheet memberare determined in accordance with the distance between the back surfaceof the motor 154 and the housing 14 facing thereto so as toappropriately absorb vibration of the motor 154. At this time, thebuffer member 160 is easily filled with no gap when the thickness of thewhole buffer member 160 is larger than the distance between the backsurface of the motor 154 and the housing 14 facing thereto.

4. Conclusion

Hereinabove, the phosphor wheel 150 in the light source unit 10 of theimage display device 1 according to an embodiment of the presentdisclosure has been described. According to the present embodiment, thebuffer member 160 is filled between the back surface of the motor 154and the housing 14 facing thereto in order to reduce noise in a highfrequency band generated by vibration of the motor of the phosphor wheel150. Thus, vibration of the motor 154 is hardly propagated to thehousing 14, and therefore it is possible to reduce noise in the highfrequency band. The buffer member 160 may be formed by bonding aplurality of sheet members. At this time, when a sheet member on themotor 154 side is formed to be softer than a sheet member on the housing14 side, it is possible to absorb vibration of the motor 154 moreeffectively.

The preferred embodiment(s) of the present disclosure has/have beendescribed above with reference to the accompanying drawings, whilst thepresent disclosure is not limited to the above examples. A personskilled in the art may find various alterations and modifications withinthe scope of the appended claims, and it should be understood that theywill naturally come under the technical scope of the present disclosure.

For example, in the above embodiment, the case where the buffer member160 is provided in the phosphor wheel 150 of the light source unit 10has been described. However, this technique is not limited to thisexample. For example, this technique may be applied to a color wheel orthe like.

Further, the effects described in this specification are merelyillustrative or exemplified effects, and are not limitative. That is,with or in the place of the above effects, the technology according tothe present disclosure may achieve other effects that are clear to thoseskilled in the art based on the description of this specification.

Additionally, the present technology may also be configured as below.

(1)

A phosphor wheel, including:

a wheel substrate that has a surface on which a fluorescent material isprovided;

a driving unit that rotates the wheel substrate;

a support portion that supports the driving unit and is fixed to ahousing; and

a buffer member that is provided to fill a space between the supportportion and a part of the housing.

(2)

The phosphor wheel according to (1), wherein

the buffer member is formed by laminating a plurality of sheet membersdifferent in hardness in a direction in which the support portion facesto a part of the housing, and

among the sheet members, a first sheet member in contact with thesupport portion is softer than a second sheet member in contact with aside of the first sheet member, the side being opposite to a side of thefirst sheet member in contact with the support portion.

(3)

The phosphor wheel according to (1) or (2),

wherein the support portion is integrally formed with a lens supportportion supporting portion a lens member for introducing light from alight source to the wheel substrate.

(4)

The phosphor wheel according to any one of (1) to (3),

wherein the buffer member is provided on a side opposite to the wheelsubstrate in a rotating shaft direction of the driving unit.

(5)

A light source unit, including:

a light source; and

a phosphor wheel that includes a fluorescent material that, when thefluorescent material is irradiated with light emitted from the lightsource, emits fluorescence emission light in a different wavelengthregion,

wherein the phosphor wheel includes

-   -   a wheel substrate that has a surface on which the fluorescent        material is provided,    -   a driving unit that rotates the wheel substrate,    -   a support portion that supports the driving unit and is fixed to        a housing, and    -   a buffer member that is provided to fill a space between the        support portion and a part of the housing.        (6)

An image display device, including:

a light source unit that includes a light source and a phosphor wheelincluding a fluorescent material that, when the fluorescent material isirradiated with light emitted from the light source, emits fluorescenceemission light in a different wavelength region; and

an optical system that projects an image formed on the basis of aluminous flux emitted from the light source unit onto a plane ofprojection,

wherein the phosphor wheel of the light source unit includes

-   -   a wheel substrate that has a surface on which a fluorescent        material is provided,    -   a driving unit that rotates the wheel substrate,    -   a support portion that supports the driving unit and is fixed to        a housing, and    -   a buffer member that is provided to fill a space between the        support portion and a part of the housing.

REFERENCE SIGNS LIST

-   1 image display device-   10 light source unit-   10A light source section-   10B cooling section-   12 a, 12 b wheel storage portion-   12 c lens support portion-   12 d motor support portion-   150 phosphor wheel-   151 wheel substrate-   152 fluorescent material-   154 motor-   160 buffer member-   162 first sheet member-   164 second sheet member

The invention claimed is:
 1. A projector, comprising: a light sourceunit; an illumination optical unit that includes at least one lensarray, a polarization conversion element and a condenser lens, whereinlight emitted from the light source unit passes through the at least onelens array, the polarization conversion element and the condenser lensand is separated for each wavelength region; and a projection lensconfigured to project the light from the light source unit via theillumination optical unit, wherein the light source unit includes awheel substrate, a housing and a buffer member that is arranged betweenthe wheel substrate and the housing along a direction of a rotatingshaft.
 2. The projector according to claim 1, wherein the light sourceunit includes a motor support member that supports a motor and is fixedto the housing.
 3. The projector according to claim 2, wherein the motorsupport member is integrally formed with a lens support membersupporting a lens for introducing the light emitted from the lightsource unit to the wheel substrate.
 4. The projector according to claim1, wherein the light source unit includes a motor support member thatsupports a motor and is fixed to the housing; and the buffer member isformed by laminating a plurality of sheet members different in hardnessin a direction in which the motor support member faces to a part of thehousing.
 5. The projector according to claim 1, wherein the light sourceunit includes a motor support member that supports a motor and is fixedto the housing; and the buffer member includes a first sheet member incontact with the motor support member that is softer than a second sheetmember in contact with a side of the first sheet member, the side beingopposite to a side of the first sheet member in contact with the motorsupport member.
 6. The projector according to claim 1, wherein the lightsource unit includes one or more light sources.
 7. The projectoraccording to claim 1, wherein the buffer member is provided on a sideopposite to the wheel substrate in a rotating shaft direction of amotor.
 8. The projector according to claim 1, wherein the wheelsubstrate has a surface on which a fluorescent material is provided. 9.The projector according to claim 8, wherein when the fluorescentmaterial is irradiated with the light emitted from the light sourceunit, it emits fluorescence emission light in a different wavelengthregion.
 10. The projector according to claim 1, wherein the illuminationoptical unit includes at least one dichroic mirror.
 11. The projectoraccording to claim 10, wherein the light emitted from the light sourceunit that has passed through the condenser lens is incident on the atleast one dichroic mirror.
 12. The projector according to claim 11,wherein the at least one lens array is arranged on an optical path ofthe light source unit and the at least one dichroic mirror is arrangedbetween the light source unit and the at least one lens array.